Customer Lifetime Value (LTV): Profit Per Account

Key Takeaways

• The standard SaaS LTV formula is ARPU multiplied by gross margin, divided by monthly churn rate.
• LTV depends on three inputs: average revenue per user, gross margin, and churn, with churn carrying the most leverage.
• The most common mistake is using revenue instead of gross profit, which inflates LTV by 30% to 70%.
• Healthy SaaS economics typically target an LTV three times the cost to acquire the customer.

What It Is

Customer lifetime value (LTV) is the discounted or undiscounted gross profit attributable to one customer over the expected life of the relationship. The metric is the cornerstone of subscription unit economics and the natural complement to customer acquisition cost when judging whether growth spending is creating or destroying value.

The simple SaaS form treats ARPU, gross margin, and churn as constants and produces a steady-state LTV. More advanced versions discount future cash flows and adjust for cohort-level differences in retention and expansion.

The Intuition

A customer who pays $100 per month and stays for five years is more valuable than one who pays $200 per month and churns after eight months. LTV combines those two effects into a single dollar figure. Anything that lengthens the relationship or raises the per-month spend pushes LTV up; anything that raises churn pushes it down.

Churn deserves special attention because it sits in the denominator. Cutting monthly churn from 5% to 2.5% does not just lower turnover; it doubles LTV. That asymmetry is why retention investments often produce a higher return than new logo acquisition once a business reaches scale.

How It Works

The most widely cited SaaS formula uses three inputs.

LTV = (ARPU x Gross Margin %) / Monthly Churn Rate

ARPU is average revenue per user, measured monthly. Gross margin converts revenue into the contribution that actually accrues to the company after delivering the service. Monthly churn rate is the percentage of customers who leave each month.

The simpler approximation drops gross margin and uses revenue alone, which inflates LTV. Most investor-grade analyses keep gross margin in the formula because acquiring a customer to deliver them service at break-even produces no value.

For businesses with net negative churn (revenue from existing customers grows faster than churn drains it), the simple formula breaks down and you need a cohort-based model that captures expansion revenue. In practice, analysts cap LTV at a 5-year or 7-year horizon to avoid runaway estimates.

Worked Example

A B2B SaaS company reports the following:

• ARPU: $500 per month
• Gross margin: 80%
• Monthly churn rate: 2%

Plugging into the formula:

• LTV = ($500 x 0.80) / 0.02 = $400 / 0.02 = $20,000

If gross margin were left out, the headline number would be $25,000, overstating value by 25%. If churn were 1% instead of 2%, LTV doubles to $40,000. A 50-basis-point swing in monthly churn shifts the LTV by 50% in either direction, which is why retention is the single most leveraged metric in the model.

For a consumer subscription at $15 per month, 70% gross margin, and 5% monthly churn, LTV is $210. The lower price point and higher churn together drop the figure by two orders of magnitude versus the B2B example.

Common Mistakes

1. Using revenue instead of gross profit. Skipping the gross margin term inflates LTV by the full cost-of-service percentage. For a 60%-margin business that is a 67% overstatement of the real economic number.
2. Holding churn constant in the model when it varies by cohort. Older, more loyal customers churn less than newer ones. A single average churn rate paints a blended picture that misses what is happening at the edges.
3. Ignoring expansion revenue. Businesses with net negative churn (Snowflake-style usage growth, for example) have LTVs that the simple formula massively understates. Use cohort analysis or net revenue retention to capture the upside.
4. Comparing to CAC without alignment of time period. If LTV is annualized and CAC reflects a single quarter, the ratio is meaningless. Use the same horizon for both.
5. Treating LTV as a forecast. LTV is a steady-state estimate that assumes today's economics hold forever. It is useful for relative comparisons and target setting, not for line-item forecasting.

Frequently Asked Questions

What is customer lifetime value (LTV) in simple terms? It is the total profit a customer is expected to generate for a company across the entire time they stay subscribed. The figure combines how much they pay, how much it costs to serve them, and how long they stick around.

How does customer lifetime value affect investment decisions? Investors use LTV to judge unit economics and the long-run return on growth spending. A company with high LTV relative to acquisition cost can keep spending on marketing aggressively, while one with low LTV needs to either lower CAC, raise ARPU, or improve retention before it scales.

What is a real-world example of customer lifetime value? A consumer streaming service might calculate LTV near $200 with $12 monthly ARPU, 60% gross margin, and 4% monthly churn. A B2B SaaS platform with $1,000 monthly ARPU, 80% gross margin, and 1% monthly churn produces an LTV near $80,000.

How can investors use customer lifetime value effectively? Always pair LTV with CAC and check that both use the same time horizon and customer cohort. Look for cohort-level disclosure rather than single blended numbers, and stress-test the result against a higher churn assumption.

How is customer lifetime value different from average revenue per user? ARPU measures one period of billing. LTV measures the cumulative gross profit across the entire customer relationship, weighting it by churn and gross margin to produce a single dollar figure.

Sources

1. ChartMogul. Customer Lifetime Value (LTV): SaaS Metrics. https://chartmogul.com/saas-metrics/ltv/
2. Wall Street Prep. Customer Lifetime Value (CLV): Formula and Calculator. https://www.wallstreetprep.com/knowledge/lifetime-value-ltv/
3. Growth Equity Interview Guide. Customer Lifetime Value (LTV) for SaaS: Formula and Benchmarks. https://growthequityinterviewguide.com/growth-equity/saas-metrics/saas-ltv
4. ChurnZero. Lifetime Value (LTV or CLTV) Formula and Example. https://churnzero.com/churnopedia/lifetime-value-ltv-or-customer-lifetime-value-cltv/

Disclaimer

This article is educational content only and is not financial advice. Nothing here is a recommendation to buy, sell, or hold any security. Consult a licensed advisor before making investment decisions.